1. Field of the Invention
The present invention relates to the field of rotary fluid distribution. More particularly, the present invention relates to rotors which can be used to distribute fluid in regenerative heat exchangers, rotary air dehumidifiers, regenerative thermal oxidizers and simulated or real moving bed devices.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
The main bodies of certain classes of process equipment need to be regenerated or renewed after a certain time period of operation. This equipment can include regenerative heat exchangers, regenerative thermal oxidizers, moving bed (simulated or real) chemical reactors/chromatographic separators, pressure swing absorption columns and regenerative air dehumidifiers. The regeneration methods include rotating the main body of the equipment or switching on and off a multitude of valves so that different sections of the main body can be contacted by different kinds of fluids at different times. The present invention attempts to alleviate the problems associated with switching on and off the multitude of valves, and to simplify rotary mechanisms of rotary valves.
Heat exchangers with rotating bodies, commonly known as Ljungstrom air preheaters, are well known in the prior art. In these types of rotary regenerators, the body (matrix) rotates continuously with the constant fraction of the core and the hot fluid stream in one section and the remaining fraction in the cold fluid stream. The outlet fluid temperatures vary across the flow area and are independent of time. The two fluids generally flow in opposite directions and are separated by some form of duct work and seals on the matrix body.
Heat exchangers with rotating hoods, or Rothemuhle regenerators, are also commonly known. The heating plate elements in this type of regenerative air preheater are installed in a casing, but the heating plate elements are stationary rather than rotating. Instead, the air ducts in the preheater are rotated so as to alternatively expose sections of the heating plate elements to the up flowing cool air. There are rotating inlet air ducts at the bottom of the stationary plate similar to the rotating outlet air ducts at the top of the stationary plates.
Rotary dehumidifiers are also commonly used. Instead of the exchange of heat or energy, a rotary dehumidifier exchanges molecules of two streams via a rotating body of desiccant or a molecular sieve.
Various patents have issued in the past relating to regenerative heat exchangers, heat engines, and regenerative thermal oxidizers. For example, U.S. Pat. No. 5,664,620, issued on Sep. 9, 1997 to Ritter, describes a rotary regenerative heat exchanger. The rotor of the rotary regenerative air preheater is constructed for the loading of the heat exchange basket modules into the sectors of the rotor in a radial direction through the periphery of the rotor. The heat exchange basket modules are arranged in a plurality of axially spaced layers with the lower baskets supporting the baskets located above. To provide the support and to facilitate the loading of the baskets, each basket includes an integral grating structure at the top surface thereof which extends partially above the uppermost surface of the basket frame. This provides a clear sliding surface as well as a support for the baskets in the layer above.
U.S. Pat. No. 6,675,871, issued on Jan. 13, 2004 to Okano et al., teaches a heat exchanger. The heat exchanger includes a honeycomb rotor, a drive unit and a gas movement device. The honeycomb rotor has at least two heat exchange passages and at least two purge zones provided respectively between the heat exchange passages. The drive unit rotates the honeycomb rotor. The gas movement device circulates a gas through the purge zones. The gas movement device may include a blower, and the drive unit may include a motor. In this case rotation of the blower can be synchronized with rotation of the motor. A drive device includes a power source that emits exhaust gas. The power source has a fuel battery having an air intake. Heat may be exchanged between the exhaust gas and air supplied to the air intake.
U.S. Pat. No. 5,335,497, issued on Aug. 9, 1994 to Macomber, describes a rotary Stirling cycle engine. The rotary Stirling cycle engine has a pair of hollow chambers each having an elliptical rotor positioned inside and rotatably sealed to the chambers inner walls. A crankshaft connects the rotors in tandem to transmit rotational energy when the rotors revolve around the chambers. A cooling and a heating heat exchanger are each connected through ports in the chambers sidewalls one to the other. Working fluid is present at a constant volume within the chambers and heat exchangers, revolving the rotors as the volume in each chamber changes due to the cyclic expansion, and contraction of the working fluid as it sweeps around the chambers through the ports while being alternately heated and cooled by the heat exchangers.
U.S. Pat. No. 7,874,175, issued on Jan. 25, 2011 to Graf, describes a heat engine and heat pump using centrifugal fans. The device comprises two doubly connected chambers. Blades in each chamber substantially rotate with the chamber and may be firmly attached to the walls of the chamber, thus forming a modified centrifugal pump with axial input and discharge. An expandable fluid is rotated outward by one of the pumps and then heat is added for an engine or removed for a heat pump as the fluid is being sent to the outer part of the second pump. The fluid travels toward the center of the second pump, thus impelling the pump in the rotation direction. Then heat is removed for an engine or added for a heat pump as the fluid leaves the second pump and travels back to the first pump near the center of rotation of both pumps. Rotation energy of the fluid is typically much larger than the circulation energy. A modified centrifugal pump with axial discharge having a casing rotating with the blades is also claimed.
U.S. Pat. No. 3,706,812, issued on Dec. 19, 1972 to Armand J. de Rosset et al., describes a rotary valve for distributing fluids to multitude of adsorption columns. This type of device allowed first generation of simulated moving bed to become operational.
U.S. Pat. No. 7,284,373, issued on Oct. 23, 2007 to Benson, describes a thermodynamic cycle engine. The thermodynamic cycle heat engine has a regenerator housing with two bidirectional regenerators, compression and expansion chambers connected to different ends of the housing, and a gear train. Each of the bi-directional regenerators comprises a low pressure connection having a first volume and a high pressure connection having a second volume less than the first volume. The bi-directional regenerators, the compression chamber, and the expansion chamber form a closed space for a working fluid. The gear train is disposed within the regenerator housing and comprises a plurality of non-round gears, a center gear group, and two outer gear groups substantially opposed with respect to the center gear group. The gear train oscillatingly rotates rotors in the chambers to create cyclically varying volumes for compression and expansion spaces so that two thermodynamic cycles are completed by the engine for each rotation of the rotors.
U.S. Pat. No. 7,937,939, issued on May 10, 2011, also to Benson, describes a bicycle thermodynamic engine. The thermodynamic cycle heat engine includes a regenerator, a chamber in fluid communication with the regenerator, first and second rotors within the chamber, forming at least a pair of spaces within the chamber, and at least one actuator. The regenerator and the chamber form a portion of a closed space for a working fluid, the actuator is arranged to displace the rotors about an axis of rotation for the rotors, and at least a portion of the actuator is fixedly secured to the rotors. In some aspects, the actuator is arranged to receive energy from the rotors and operate as a generator, or a sensor is arranged to detect a condition associated with operation of the chamber and a controller is arranged to control the actuator responsive to the detected condition. In some aspects, the engine includes a heat exchanger in fluid communication between the regenerator and the chamber.
U.S. Pat. No. 7,141,712, issued on Nov. 28, 2006 to Wang et al., summarizes various valve options for simulated moving bed chromatography technology. Both single rotary valves and distributed valve systems were described.
U.S. Pat. No. 5,967,771, issued on Oct. 19, 1999 to Chen et al., describes a rotary regenerative oxidizer and system thereof. The system for the abatement of industrial process gases utilizes a rotary regenerative oxidizer comprised of one or more heat exchange beds, each bed comprised of a parallel, axial, and longitudinal array of heat regenerative channels that thermally and/or catalytically oxidize contaminated gases. Utilizing a rotary regenerative oxidizer, and if desired, a plurality of heat regenerative beds incorporated therein, facilitates the use of regenerative technology at lower gas flow rates, increases thermal efficiency, and significantly reduces the floor space normally required when implementing fixed-bed nonrotary regenerative oxidizers. The heat exchange channels may be catalytically treated to enhance oxidation of the pollutants at a lower temperature. U.S. Pat. No. 5,871,347, issued on Feb. 16, 1999 also to Chen et al., describes a similar rotary regenerative oxidizer.
U.S. Pat. No. 6,193,504, issued on Feb. 27, 2001 also to Chen et al., teaches a portable rotary catalytic oxidizer system. The rotary regenerative catalytic oxidizer catalytically destroys VOC and odorous compounds at elevated temperatures of 400 to 800° F. Equipped with a very high thermally efficient rotor of 90+%, most heat for reaction is retained in the apparatus, and the cleaned air at temperatures of 80 to 120° F. is safely discharged into room without causing discomfort. As a portable unit, it can be used to treat local areas where odorous and/or hazardous VOC and CO compounds are present and conveniently run off household 120V or 220V systems.
U.S. Pat. No. 7,762,808, issued on Jul. 27, 2010 to Lee et al., also describes a regenerative thermal oxidizer. The regenerative thermal oxidizer burns and eliminates harmful process gases generated in industrial sites. The apparatus has different parts of the rotor that are used as inlet and outlet process gas flowpaths to increase the ability to process the process gases.
It is an object of the present invention to provide a rotary fluid distributor which allows a pair of rotors to accomplish the task which previously required multiple valves.
It is another object of the present invention to provide rotary fluid distributors which achieve greater productivity.
It is another object of the present invention to provide rotary fluid distributors that allow the direction of the fluid introduced into a heat exchanger to be altered, rather than rotation of the heat absorbing material therein.
It is another object of the present invention to provide a rotary fluid distributor that can be used in simulated moving bed chromatography.
It is another object of the present invention to provide a rotary fluid distributor having a pair of synchronized rotors.
It is a further object of the present invention to provide a fluid distributor rotor that eliminates the need to rotate the main body of regenerative equipment.
It is another object of the present invention to provide a rotary fluid distributor that can be easily installed and maintained.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.